Weapon Auto-aim and Lockboxes

Heya, folks. I have a feeling that I'm missing a setting or hotkey here, so user error, most likely. However, my weapons keep aiming for the center of lockboxes (even when I don't have them targeted) so that I cannot shoot the individual locks off. Is there a way to boresight them or something? I turned auto-aim off, but that didn't stop them from tracking right onto the center of the box again.